This article highlights seven interesting things you can see if you look closely at masterpieces. It includes paintings with a baby flipping off the pope, UFO's in the sky, and the shape of a brain that surrounds God as painted on the ceiling of the Sistine Chapel.
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From the Upcoming ueue, submitted by dentboy324.
While some might dismiss this as a coincidence, experts suggest that it would be harder to explain that this was not Michelangelo's intention. Even complex components within the brain, such as the cerebellum, optic chiasm and pituitary gland can all be found in the picture. As for that sassy green sash running down the pons/spinal column/dude-holding-God-up, it follows the path of the vertebral artery perfectly.
Along with drawing, painting, sculpting, St. Peter's Basilica building and generally being among the universe's top bananas, Michelangelo counted cadaver dissecting as a favorite way to pass the time. He was so mad about corpse-cutting, in fact, that a friend once presented him with a perfectly formed dead Moor as a gift.
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One thing you have to look out for: people telling you what you're supposed to see. The power of suggestion is very strong.